CN115502416A - Heat treatment method for GH4099 high-temperature alloy formed by selective laser melting - Google Patents

Abstract

The present application discloses a heat treatment method for a GH4099 superalloy formed by laser selective melting, the method comprising: setting hot isostatic pressing parameters, and performing hot isostatic pressing on the laser selective melting and forming GH4099 superalloy based on the hot isostatic pressing parameters, In order to eliminate the defects inside the GH4099 superalloy that affect the fineness of the GH4099 superalloy; set solution treatment parameters and aging treatment parameters, perform solution treatment on the GH4099 superalloy based on the solution treatment parameters, and perform aging on the GH4099 superalloy based on the aging treatment parameters Treating the treated GH4099 superalloy. The application solves the technical problem in the prior art that the properties of the GH4099 superalloy formed by laser selective melting cannot meet the actual needs.

Description

A heat treatment method for GH4099 superalloy formed by laser selective melting

technical field

The present application relates to the technical field of material processing, in particular to a method for heat treatment of GH4099 superalloy formed by selective laser melting.

Background technique

GH4099 is a typical nickel-based superalloy with excellent high-temperature mechanical properties, creep resistance and corrosion resistance. GH4099 superalloy has good high-temperature mechanical properties after solution aging treatment. It can be used for a long time below 900°C, and the maximum working temperature can reach 1000°C. It is an important metal material in the aerospace field. The GH4099 alloy is mainly composed of Ni and Cr elements, which are solid solution strengthened by W, Mo, Co and other elements, aged strengthened by Al and Ti, and grain boundary strengthened by B. After solid solution and aging treatment, the γ phase is formed. The complex structure of the matrix and other compound phases can meet the requirements of aerospace high-temperature structural parts. Laser selective melting forming technology is an additive manufacturing technology that uses laser as an energy source to continuously melt-solidify and accumulate metal powder to obtain products. It has the advantages of high efficiency, high precision, high design freedom, and low cost. It can form high-temperature alloys, titanium alloys, aluminum alloys and other materials, and has been widely used in the aerospace field.

Laser selective melting forming GH4099 superalloy can be applied to high-temperature structural parts such as rudder wings and engine combustion chambers. The GH4099 superalloy obtained by selective laser melting is a deposited GH4099 superalloy, and there are defects such as holes and microcracks in the deposited GH4099 superalloy. These internal defects reduce the density of the alloy, and stress concentration will occur when the structural parts are in service. , become the source of cracks and reduce the strength, plasticity and fatigue performance of structural parts. In addition, the as-deposited GH4099 superalloy has a submicron-scale cellular structure, which is conducive to improving the mechanical properties of the alloy at room temperature, but reduces the high-temperature strength and plasticity of the alloy, which cannot meet the application requirements, as shown in Figure 1A and Figure 1B. Among them, Figure 1A shows a schematic diagram of the interior of the laser selective melting forming GH4099 superalloy perpendicular to the forming direction; Figure 1B shows a schematic diagram of the interior of the laser selective melting forming GH4099 superalloy parallel to the forming direction.

Contents of the invention

The technical problem solved by this application is: the performance of the GH4099 superalloy formed by laser selective melting in the prior art cannot meet the actual demand. This application provides a heat treatment method for laser selective melting and forming of GH4099 superalloy. In the scheme provided in the embodiment of this application, defects such as holes and microcracks of laser selective melting and forming of GH4099 superalloy are eliminated by hot isostatic pressing treatment, and the improvement is improved. Improve the fine density of the GH4099 superalloy, which is conducive to improving the mechanical properties of the alloy; and/or through solution treatment and aging treatment, the cellular structure of the GH4099 superalloy formed by laser selective melting can be transformed into a fine equiaxed grain structure, forming in the matrix A large number of fine and dispersed γ' strengthening phases improve the toughness and plasticity of the GH4099 superalloy, thereby improving the performance of the GH4099 superalloy.

In the first aspect, the embodiment of the present application provides a heat treatment method for laser selective melting forming GH4099 superalloy, the method includes:

Set the hot isostatic pressing treatment parameters, based on the hot isostatic pressing treatment parameters, perform hot isostatic pressing treatment on the laser selective melting and forming GH4099 superalloy, to eliminate the influence of the fine density of the GH4099 superalloy inside the GH4099 superalloy defects; and/or

Set solution treatment parameters and aging treatment parameters, perform solution treatment on the GH4099 superalloy based on the solution treatment parameters, and perform aging treatment on the GH4099 superalloy based on the aging treatment parameters to obtain the treated GH4099 superalloy .

Optionally, the hot isostatic pressing parameters include: hot isostatic pressing temperature, pressure and first holding time, wherein the hot isostatic pressing temperature ranges from 1000°C to 1200°C, and the first holding time The value range of time is 2 hours to 4 hours, and the value range of pressure is 90MPa～130MPa;

The solution treatment parameters include the first heating rate, the first solution temperature, the second holding time, the first cooling rate and the first vacuum degree; wherein, the value range of the first heating rate is 2°C/min～ 15°C/min, the value range of the first solution temperature is 1100°C-1300°C, the value range of the second holding time is 1 hour-3 hours, and the value range of the first cooling rate is 55°C /min-120°C/min, the precision of the first vacuum degree is 10 ^-2 Pa.

The aging treatment parameters include a second heating rate, a second solid solution temperature, a third holding time, a second cooling rate, and a second vacuum degree; wherein, the second heating rate ranges from 5°C/min to 10°C. °C/min, the value range of the second solid solution temperature is 720 °C to 780 °C, the value range of the third holding time is 6 hours to 10 hours, and the value range of the second cooling rate is 10 °C/min min to 20°C/min, and the accuracy of the second vacuum degree is 10 ^-2 Pa.

Optionally, wherein, the hot isostatic pressing temperature is set to 1050° C., the pressure is set to 90 MPa, and the first heat preservation is set to 2 hours.

Optionally, wherein the hot isostatic pressing temperature is set to 1200° C., the pressure is set to 100 MPa, and the first heat preservation is set to 3 hours.

Optionally, based on the hot isostatic pressing treatment parameters, the hot isostatic pressing treatment is performed on the laser selective melting forming GH4099 superalloy, including:

Set the temperature in the high-temperature and high-pressure sealed container for hot isostatic pressing to 1200°C and the pressure to 100MPa;

The GH4099 superalloy was placed in the high-temperature and high-pressure sealed container, and kept warm for 3 hours to realize the hot isostatic pressing treatment of the GH4099 superalloy.

Optionally, performing solution treatment on the GH4099 superalloy based on the solution treatment parameters includes: transforming the submicron-scale cellular structure in the GH4099 superalloy into an axial grain structure.

Optionally, wherein, the first heating rate is set to 2°C/min, the first solid solution temperature is 1100°C, the second holding time is 1 hour, and the first cooling rate is 55°C/min min and the first vacuum degree is 5×10 ^-2 Pa.

Optionally, wherein, the first heating rate is set to 5°C/min, the first solid solution temperature is 1250°C, the second holding time is 1.5 hours, and the first cooling rate is 65°C/min min and the first vacuum degree is 5×10 ^{- 2} Pa.

Optionally, wherein, the value range of the second heating rate is set to 5°C/min, the value range of the second solid solution temperature is 720°C, and the value range of the third holding time is 6 hours, so The value range of the second cooling rate is 10°C/min, and the precision of the second vacuum degree is 5×10 ^-2 Pa.

Optionally, wherein, the value range of the second heating rate is set to 5°C/min, the value range of the second solid solution temperature is 730°C, and the value range of the third holding time is 7 hours, so The value range of the second cooling rate is 10°C/min, and the precision of the second vacuum degree is 5×10 ^-2 Pa.

In the solution provided by the embodiment of the present application, the hot isostatic pressing treatment eliminates the holes, microcracks and other defects of the laser selective melting forming GH4099 superalloy, improves the fineness density of the GH4099 superalloy, and is conducive to improving the mechanical properties of the alloy and/or through solution treatment and aging treatment, transform the cellular structure of the GH4099 superalloy formed by laser selective melting into a fine equiaxed grain structure, form a large number of fine and dispersed γ' strengthening phases in the matrix, and improve the toughness of the GH4099 superalloy And plasticity, thereby improving the performance of GH4099 superalloy.

Description of drawings

Figure 1A shows a schematic diagram of the laser selective melting forming GH4099 superalloy interior perpendicular to the forming direction;

Figure 1B shows a schematic diagram of the laser selective melting forming GH4099 superalloy inside parallel to the forming direction;

Fig. 2 is a schematic flow chart of a heat treatment method for a laser selective melting forming GH4099 superalloy provided in an embodiment of the present application.

detailed description

In the solutions provided by the embodiments of the present application, the described embodiments are only some of the embodiments of the present application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

In order to better understand the above technical solutions, the technical solutions of the present application will be described in detail below through the accompanying drawings and specific examples. It should be understood that the embodiments of the present application and the specific features in the examples are detailed descriptions of the technical solutions of the present application, and It is not a limitation to the technical solutions of the present application, and the embodiments of the present application and the technical features in the embodiments can be combined without conflict.

The following is a further detailed description of a laser selective melting and forming GH4099 superalloy heat treatment method provided in the embodiment of the present application in conjunction with the accompanying drawings. The specific implementation of the method may include the following steps (the process flow is shown in Figure 2):

Step 201, setting hot isostatic pressing parameters, and performing hot isostatic pressing on the GH4099 superalloy formed by laser selective melting based on the hot isostatic pressing parameters, so as to eliminate the internal influence of the GH4099 superalloy on the GH4099 superalloy. Density defects.

It can be seen from the above Figures 1A and 1B that the GH4099 superalloy obtained based on the laser selective melting forming technology may or may have defects that affect the fineness of the GH4099 superalloy, such as holes, bubbles, and microcracks. Hot isostatic pressing technology is a kind of modern material forming technology and a branch of isostatic pressing technology. Isostatic pressing technology is generally divided into cold isostatic pressing, warm isostatic pressing and hot isostatic pressing according to the level of forming and consolidation temperature. Hot isostatic pressing is in a high-temperature and high-pressure sealed container, using high-pressure gas as the medium, applying uniform static pressure in all directions to the powder or sintered billet (or part) to be compacted to form a high-density billet or part.

Since the hot isostatic pressing is in a high-temperature and high-pressure sealed container, when performing hot isostatic pressing on the laser selective melting and forming GH4099 superalloy, it is necessary to set the hot isostatic pressing parameters, for example, the environmental parameters in the high-temperature and high-pressure sealed container (such as when performing hot isostatic pressing, the temperature and pressure in the high-temperature and high-pressure sealed container) and/or other parameters (such as time parameters), etc.

As an example, setting the hot isostatic pressing treatment parameters includes: hot isostatic pressing temperature, pressure, and first holding time, wherein the hot isostatic pressing temperature ranges from 1000°C to 1200°C, and the first holding time takes a value of The range is 2 hours to 4 hours, and the pressure range is 90MPa to 130MPa;

As another example, the hot isostatic pressing temperature is set to 1050° C., the pressure is set to 90 MPa, and the first heat preservation is set to 2 hours. Or set the hot isostatic pressing temperature to 1200° C., the pressure to 100 MPa, and the first heat preservation to 3 hours.

As another example, based on the hot isostatic pressing treatment parameters, the hot isostatic pressing treatment is performed on the GH4099 superalloy formed by laser selective melting, including: setting the temperature in the high-temperature and high-pressure sealed container for hot isostatic pressing treatment to 1200 ° C, and the pressure is 100MPa; the GH4099 superalloy is placed in the high-temperature and high-pressure sealed container, and kept warm for 3 hours to realize the hot isostatic pressing treatment of the GH4099 superalloy.

Further, by performing hot isostatic pressing on the GH4099 superalloy formed by laser selective melting, the defects inside the GH4099 superalloy that affect the fineness of the GH4099 superalloy can be eliminated, thereby increasing the fineness of the GH4099 superalloy.

Step 202, setting solution treatment parameters and aging treatment parameters, performing solution treatment on the GH4099 superalloy based on the solution treatment parameters and performing aging treatment on the GH4099 superalloy based on the aging treatment parameters to obtain the treated GH4099 superalloy.

In the solution provided in the examples of this application, the laser selective melting forming GH4099 superalloy has a submicron-scale cellular structure, which is conducive to improving the mechanical properties of the alloy at room temperature, but reduces the high-temperature strength and plasticity of the alloy, which cannot meet the requirements of the application. Require. Therefore, in order to improve the high-temperature strength and plasticity of the GH4099 superalloy, it is necessary to carry out solid solution and aging treatment on the GH4099 superalloy. In order to facilitate understanding, the processes of solution treatment and aging treatment are briefly introduced below.

1. Solid solution treatment

Solution treatment refers to a heat treatment process in which the alloy is heated to a high temperature and kept at a constant temperature in a single zone, so that the excess phase is fully dissolved into the solid solution and then rapidly cooled to obtain a supersaturated solid solution. Solution treatment fully dissolves various phases in the alloy, strengthens the solid solution, improves and improves the plasticity and toughness of the alloy, eliminates stress and softens, and prepares for precipitation hardening treatment.

Further, in order to realize solution treatment, it is necessary to set solution treatment parameters. Solution treatment parameters include, for example, the first heating rate, the first solution temperature, the second holding time, the first cooling rate, and the first vacuum degree; wherein, the value range of the first heating rate is 2°C/min～15 °C/min, the value range of the first solid solution temperature is 1100 °C to 1300 °C, the value range of the second holding time is 1 hour to 3 hours, and the value range of the first cooling rate is 55 °C/min min-120°C/min, the precision of the first vacuum degree is 10 ^-2 Pa.

As an example, set the first heating rate to 2°C/min, the first solid solution temperature to 1100°C, the second holding time to 1 hour, the first cooling rate to 55°C/min and the The first vacuum degree is 5×10 ^-2 Pa. As another example, set the first heating rate to 5°C/min, the first solid solution temperature to 1250°C, the second holding time to 1.5 hours, the first cooling rate to 65°C/min and The first vacuum degree is 5×10 ^-2 Pa.

2. Aging treatment

Aging treatment refers to the heat treatment process in which the alloy workpiece is placed at a higher temperature or at room temperature after solution treatment, cold plastic deformation, casting, and forging, and its performance, shape, and size change with time. The purpose of aging treatment is to eliminate the internal stress of the workpiece, stabilize the structure and size, and improve the mechanical properties.

Further, in order to realize the aging treatment, it is necessary to set the aging treatment parameters. The aging treatment parameters include, for example, the second heating rate, the second solid solution temperature, the third holding time, the second cooling rate, and the second vacuum degree; wherein, the second heating rate ranges from 5°C/min to 10°C /min, the value range of the second solid solution temperature is 720°C to 780°C, the value range of the third holding time is 6 hours to 10 hours, and the value range of the second cooling rate is 10°C/min ~20°C/min, the precision of the second vacuum degree is 10-2Pa.

As an example, the value range of the second heating rate is set to 5°C/min, the value range of the second solid solution temperature is 720°C, the value range of the third holding time is 6 hours, and the second The value range of the cooling rate is 10°C/min, and the precision of the second vacuum degree is 5×10 ^-2 Pa. As another example, the value range of the second heating rate is set to 5°C/min, the value range of the second solid solution temperature is 730°C, the value range of the third holding time is 7 hours, and the value range of the first The value range of the second cooling rate is 10°C/min, and the accuracy of the second vacuum degree is 5×10 ^-2 Pa.

Through solid solution aging treatment, the submicron-scale cellular structure in GH4099 superalloy is transformed into fine equiaxed crystals, and a fine, dispersedly distributed γ' strengthening phase is formed inside the matrix, and laser selective melting with excellent mechanical properties at room temperature and high temperature is obtained. Forming GH4099 superalloy products.

In the solution provided in the embodiment of the present application, the hot isostatic pressing treatment, solution treatment and aging treatment of the GH4099 superalloy can be used alone or in combination according to actual needs or requirements, and are not limited here. In addition, for the hot isostatic pressing treatment, solution treatment and aging treatment of the GH4099 superalloy, different processing parameters can be set according to actual needs, and the properties of the treated GH4099 superalloy obtained for different processing parameters are also different.

As an example, hot isostatic pressing treatment is performed on the GH4099 superalloy formed by laser selective melting. The temperature is 2°C/min, the solid solution temperature is 1100°C, the holding time is 1h, the cooling rate is 55°C/min, and the vacuum degree is 5×10 ^-2 Pa; the aging treatment is performed on the GH4099 superalloy formed by laser selective melting, and the heating rate is 5°C/min, the solid solution temperature is 720°C, the holding time is 6h, the cooling rate is 10°C/min, and the vacuum degree is 5×10 ^-2 Pa. It is verified by experiments that under the treatment parameters, the density of the GH4099 superalloy formed by laser selective melting after the enhanced heat treatment is 99.99%, the tensile strength of the alloy at room temperature is 1120MPa, the yield strength is 813MPa, the elongation is 31%, and the tensile strength at 950°C It is 306MPa, the yield strength is 223MPa, and the elongation is 23%.

As another example, carry out hot isostatic pressing treatment on the GH4099 superalloy formed by laser selective melting, the hot isostatic pressing temperature is 1200°C, the holding time is 3h, and the pressure is 100MPa; The rate is 5°C/min, the solid solution temperature is 1250°C, the holding time is 1.5h, the cooling rate is 65°C/min, and the vacuum degree is 5×10 ^-2 Pa; aging treatment is performed on the GH4099 superalloy formed by laser selective melting, and the temperature is raised The rate is 5°C/min, the solid solution temperature is 730°C, the holding time is 7h, the cooling rate is 10°C/min, and the vacuum degree is 5×10 ^-2 Pa. It is verified by experiments that under the treatment parameters, the density of the GH4099 superalloy formed by laser selective melting after the enhanced heat treatment is 99.99%, the tensile strength of the alloy at room temperature is 1150MPa, the yield strength is 825MPa, the elongation is 33%, and the tensile strength at 950°C is 310MPa, the yield strength is 215MPa, and the elongation is 21%.

In the solution provided by the embodiment of the present application, the hot isostatic pressing treatment eliminates the holes, microcracks and other defects of the laser selective melting forming GH4099 superalloy, improves the fineness density of the GH4099 superalloy, and is conducive to improving the mechanical properties of the alloy and/or through solution treatment and aging treatment, transform the cellular structure of the GH4099 superalloy formed by laser selective melting into a fine equiaxed grain structure, form a large number of fine and dispersed γ' strengthening phases in the matrix, and improve the toughness of the GH4099 superalloy And plasticity, thereby improving the performance of GH4099 superalloy.

Those skilled in the art should understand that the embodiments of the present application may be provided as methods, systems, or computer program products. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowcharts and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present application. It should be understood that each procedure and/or block in the flowchart and/or block diagram, and a combination of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a An apparatus for realizing the functions specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart or blocks of the flowchart and/or the block or blocks of the block diagrams.

Obviously, those skilled in the art can make various changes and modifications to the application without departing from the spirit and scope of the application. In this way, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these modifications and variations.

Claims (10)

1. A heat treatment method for GH4099 high-temperature alloy formed by selective laser melting is characterized by comprising the following steps:

setting hot isostatic pressing parameters, and carrying out hot isostatic pressing treatment on the GH4099 high-temperature alloy formed by selective laser melting based on the hot isostatic pressing parameters so as to eliminate the defect that the fine density of the GH4099 high-temperature alloy is influenced in the GH4099 high-temperature alloy; and/or

Setting a solid solution treatment parameter and an aging treatment parameter, carrying out solid solution treatment on the GH4099 high-temperature alloy based on the solid solution treatment parameter, and carrying out aging treatment on the GH4099 high-temperature alloy based on the aging treatment parameter to obtain the treated GH4099 high-temperature alloy.

2. The method of claim 1, wherein the hot isostatic pressing parameters comprise: hot isostatic pressing temperature, pressure and first heat preservation time, wherein the hot isostatic pressing temperature ranges from 1000 ℃ to 1200 ℃, the first heat preservation time ranges from 2 hours to 4 hours, and the pressure ranges from 90MPa to 130MPa;

the solid solution treatment parameters comprise a first heating rate, a first solid solution temperature, a second heat preservation time, a first cooling speed and a first vacuum degree; wherein the first heating rate value range is 2 ℃/min to 15 ℃/min, the first solid solution temperature value range is 1100 ℃ to 1300 ℃, the second heat preservation time value range is 1 hour to 3 hours, the first cooling rate value range is 55 ℃/min to 120 ℃/min, and the first vacuum degree precision is 10 to 2Pa;

the aging treatment parameters comprise a second heating rate, a second solid solution temperature, a third heat preservation time, a second cooling speed and a second vacuum degree; wherein the second heating rate value range is 5 ℃/min to 10 ℃/min, the second solid solution temperature value range is 720 ℃ to 780 ℃, the third heat preservation time value range is 6 hours to 10 hours, the second cooling rate value range is 10 ℃/min to 20 ℃/min, and the second vacuum degree precision is 10 DEG C ^-2 Pa。

3. The method of claim 2, wherein the hot isostatic pressing temperature is set at 1050 ℃, the pressure is set at 90MPa, and the first holding time is set at 2 hours.

4. The method of claim 2, wherein the hot isostatic pressing temperature is set at 1200 ℃, the pressure is set at 100MPa, and the first holding time is set at 3 hours.

5. The method of claim 3, wherein hot isostatic pressing the selectively laser melted GH4099 high temperature alloy based on the hot isostatic pressing parameters comprises:

setting the temperature in a high-temperature high-pressure sealed container for realizing hot isostatic pressing treatment to be 1200 ℃ and the pressure to be 100MPa;

and (3) placing the GH4099 high-temperature alloy in the high-temperature high-pressure sealed container, and preserving heat for 3 hours to realize hot isostatic pressing treatment on the GH4099 high-temperature alloy.

6. The method of any one of claims 2 to 5, wherein the solution treatment of the GH4099 superalloy based on the solution treatment parameters comprises:

converting submicron cellular structure in the GH4099 superalloy into axial crystal structure.

7. The method according to any one of claims 2 to 5, wherein the first temperature rise rate is set to 2 ℃/min, the first solid-solution temperature is set to 1100 ℃, the second holding time is set to 1 hour, the first cooling rate is set to 55 ℃/min and the first vacuum degree is set to 5 x 10 ^-2 Pa。

8. The method according to any one of claims 2 to 5, wherein the first temperature raising rate is set to 5 ℃/min, the first solid-solution temperature is 1250 ℃, the second holding time is 1.5 hours, the first cooling rate is set to 65 ℃/min and the first vacuum degree is set to 5 x 10 ^-2 Pa。

9. The method according to any one of claims 2 to 5, wherein the second temperature rise rate is set to be in a range of 5 ℃/min, the second solid solution temperature is set to be in a range of 720 ℃, the third heat preservation time is set to be in a range of 6 hours, the second cooling rate is set to be in a range of 10 ℃/min, and the second vacuum degree precision is 5 x 10 DEG C ^-2 Pa。

10. The method according to any one of claims 2 to 5, wherein the second temperature rise rate is set to be in a range of 5 ℃/min, the second solid solution temperature is set to be in a range of 730 ℃, the third holding time is set to be in a range of 7 hours, the second cooling rate is set to be in a range of 10 ℃/min, and the second vacuum degree precision is 5 x 10 ^-2 Pa。

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